Aussie (& S-Hemisphere) Cyclone Action 2010-2011

[k***]

lolz

[HurricaneJosh]

That's a pretty obtuse answer dude. Especially as the answer lies in the recording hierarchy (if you cared to look at it harder perhaps you would have seen the obvious). The US system rates 1 minute sustained winds (what we would call gusts). The Aussie system relies on 10 minute sustained winds. Think about it Josh.... and don't be so dismissive dude. That essentially brings both systems into line... or you can go on your merry dudeship way.

Actually, the BoM does not consider a 1-min wind a gust. The BoM standard for a gust is a peak 3-sec average value.

Re: 10-min winds vs. 1-min winds... Yes, we are all very aware of the difference-- if you read this thread you will see that we convert back and forth between the 10-min and 1-min all the time when making comparisons between Aussie and American measurements.

The scale comparison on Page 1-- and our discussions here-- take the 1-min/10-min difference into account. We generally use a conversion factor of 1.14 to make direct comparisons.

Look, I'm probably wrong in regard to my argument re the SS system... but either way I retire.... no point bringing a new idea (or even an old one) to an American. So I give up.

Whatever dude.

You come off hypocritically here. You busted into this conversation to insist that your scale is good and ours is wrong. We politely suggested that all scales are good-- and yours works for you and ours works for us. You insisted that we are wrong, and we should use your scale-- and that mere hubris prevents us from using your scale. And throughout, you sprinkled some pretty impolite generalizations about Americans-- on an American discussion forum.

I couldn't imagine going onto an Aussie discussion forum-- or one for any other country-- and lecturing them about how our scale is better than theirs. I don't prefer the Aussie scale, but I think it's great and it clearly works for you guys-- so why should I suggest you use the American scale? Live and let live, I say.

Perhaps look in the mirror for a moment.

[Scott747]

I was 'team boomer' for the early part of the discussion.

Then he had to go all anti-American.

[HurricaneJosh]

I was 'team boomer' for the early part of the discussion.

Then he had to go all anti-American.

It's really disappointing. I don't know why the discussion had to go in that direction.

Anyhoo... Back on topic...

Well, there's nothing much to discuss right now.

[k***]

It would have been the 87 one ( i was young and drunk)... was it named?

did you and ed mahmoud visit a gay bar in louisiana around that time?

[HurricaneJosh]

In mildly interesting news today... Carlos has finally achieved Cat-3 AUS status from the the BoM and hurricane status form the JTWC. BoM puts the intensity at 65 kt (10-min), the JTWC at 65 kt (1-min). It's out in the open Indian Ocean, just kind of doing its own thing. Blah.

[k***]

In mildly interesting news today... Carlos has finally achieved Cat-3 AUS status from the the BoM and hurricane status form the JTWC. BoM puts the intensity at 65 kt (10-min), the JTWC at 65 kt (1-min). It's out in the open Indian Ocean, just kind of doing its own thing. Blah.

It looks soooo sad...it's the elderly cyclone that no one bothers to visit anymore.

[HurricaneJosh]

It looks soooo sad...it's the elderly cyclone that no one bothers to visit anymore.

You're right, it kind of does-- out there all alone like that:

[aslkahuna]

Knots are also used in aviation. Technically, the 10 minute sustained wind criterion IS the standard-it's the US that's offline. However, there are valid reasons for this as all of our meteorological reporting and observing criteria are coordinated between all of the using agencies (Military, NWS, FAA to name a few). A war story-back in the late 1960's when the original METAR observation format came out, Air Weather Service decided to use it totally which meant going with the WMO standards thus we began using 10 minite winds in our observations overseas (CONUS stayed with Airways code). USAF went ballistic as neither the 10 minute winds nor the maximum wind reporting rules meshed with the weather limitations for various operations (plus they hadn't been consulted). We had to immediately go back to 1 minute winds and reporting visibility in miles on the local deseminations instead of meters (still used meters in transmitting the obs). Worse, yet was that after spending years getting Pilots to understand SCT/BKN/OVC we now had to teach them how to used Octas (ten years later, I was still getting pilot complaints about the "new code"). The Navy refused to go along with Metar period for years. What has always amused me is that when calculating takeoff distance, the charts use a mix of metric and English units.

Steve

[HurricaneJosh]

Knots are also used in aviation. Technically, the 10 minute sustained wind criterion IS the standard-it's the US that's offline. However, there are valid reasons for this as all of our meteorological reporting and observing criteria are coordinated between all of the using agencies (Military, NWS, FAA to name a few). A war story-back in the late 1960's when the original METAR observation format came out, Air Weather Service decided to use it totally which meant going with the WMO standards thus we began using 10 minite winds in our observations overseas (CONUS stayed with Airways code). USAF went ballistic as neither the 10 minute winds nor the maximum wind reporting rules meshed with the weather limitations for various operations (plus they hadn't been consulted). We had to immediately go back to 1 minute winds and reporting visibility in miles on the local deseminations instead of meters (still used meters in transmitting the obs). Worse, yet was that after spending years getting Pilots to understand SCT/BKN/OVC we now had to teach them how to used Octas (ten years later, I was still getting pilot complaints about the "new code"). The Navy refused to go along with Metar period for years. What has always amused me is that when calculating takeoff distance, the charts use a mix of metric and English units.

Steve

Interesting stuff-- thanks for sharing that. I also thought the 1-min average was used because engineers had decided that it took about 1 min for the wind blowing at a certain speed for it to realize its full damage potential on a structure. I could be mistaken, but I thought I read that somewhere.

By the way-- and I know this topic has come up before-- what factor do you use to convert 10-min to 1-min winds? I've always used 1.15, but it seems that's on the higher end of the range (I've seen everything from 1.11 to 1.15). Lately, for some inter-basin research, Jorge and I have been using 1.136. (This sounds like an odd number, but it's just a 1-min-->10-min factor of .88 reversed.) Thoughts?

[HurricaneJosh]

Deja vu: another Tropical Low has formed near the Kimberley and it's expected to move parallel to the coast and develop into a cyclone over the weekend. I'm getting a little bored with these coast-huggers.

The BoM also mentions that another low might form in the Gulf of Carpentaria over the weekend.

[am19psu]

Deja vu: another Tropical Low has formed near the Kimberley and it's expected to move parallel to the coast and develop into a cyclone over the weekend. I'm getting a little bored with these coast-huggers.

This is another slow developing, 45-55kt piece of junk. The wet season must be awesome over there during La Ninas.

The BoM also mentions that another low might form in the Gulf of Carpentaria over the weekend.

It probably will form, but move inland pretty quickly.

[HurricaneJosh]

This is another slow developing, 45-55kt piece of junk. The wet season must be awesome over there during La Ninas.

It probably will form, but move inland pretty quickly.

Hmmm. OK, well, I guess a break is OK. I'm still hopeful about, March-- despite the lame beginning that you're anticipating.

[Ed Lizard]

Hey Psu, How many buildings in the US are built to SS Cat 5 (above 310kph)?

The Galveston County EMS building is rated for a Cat 5 wind and likely surge. I know, because when NWS HGX moved their offices into the building, the press release stated that.

And Texas has never had a Cat 5, but we believe in better safe than sorry.

I consumed mass quantities in Freemantle/Perth in early 1985 and again Christmas 1986, hence my hopes for a Northeast style transitioning but still strong cyclone.

But most of my social media friends in Australia live in QLD. That is misleading. I know a single Facebook poster in QLD.

[am19psu]

I'm still hopeful about, March-- despite the lame beginning that you're anticipating.

Yeah, there is still the overriding ENSO factor that should mean an above normal month. Just because the MJO will start out on suppressive side doesn't mean it will be that way the whole month. I suspect the 2nd half of the month will be much more active than climo.

[HurricaneJosh]

Yeah, there is still the overriding ENSO factor that should mean an above normal month. Just because the MJO will start out on suppressive side doesn't mean it will be that way the whole month. I suspect the 2nd half of the month will be much more active than climo.

OK, cool. Any ideas Re: areas? Like, more Coral Sea/QLD or Indian Ocean/WA or...?

[Ed Lizard]

Knots are handy because doubling meters per second is very close (not exact, but close enough for reasonable use) to knots. The Utah U model page maps give winds in meters/seconds, the ECMWF free page gives 850 mb winds in m/s, just double up, and you're close enough to speed in knots for any practical home purpose.

[am19psu]

OK, cool. Any ideas Re: areas? Like, more Coral Sea/QLD or Indian Ocean/WA or...?

Crystal ball doesn't specify regions a month in advance

I'd guess we'll keep going with the WA stuff until mid-month or so and then have a better shot at getting the Coral Sea active again.

[Ed Lizard]

Yeah, there is still the overriding ENSO factor that should mean an above normal month. Just because the MJO will start out on suppressive side doesn't mean it will be that way the whole month. I suspect the 2nd half of the month will be much more active than climo.

Coral Sea and Carpinteria, maybe, by mid month?

[am19psu]

Coral Sea and Carpinteria, maybe, by mid month?

Yeah, I'd go with something like that. I'm not sure if the wave over Africa is a "real" MJO or not, but the ECM appears to show a return to P6/7 by mid-month.

[HurricaneJosh]

Knots are handy because doubling meters per second is very close (not exact, but close enough for reasonable use) to knots. The Utah U model page maps give winds in meters/seconds, the ECMWF free page gives 850 mb winds in m/s, just double up, and you're close enough to speed in knots for any practical home purpose.

Yeah, I've used that trick, too-- as a rough guide.

Crystal ball doesn't specify regions a month in advance

I'd guess we'll keep going with the WA stuff until mid-month or so and then have a better shot at getting the Coral Sea active again.

OK, sorry-- I know it's a bit silly to ask for such specifics this far out.

[aslkahuna]

For the Quick and Dirty, I use 1.15 as the factor to convert 10 min to 1 min winds. For more precision then the ratio of 1.136 should be used. OTOH at the level of windspeeds we are talking about, most anemometers have sufficient "slop" as I call it that precision is not called for.

Steve

[HurricaneJosh]

For the Quick and Dirty, I use 1.15 as the factor to convert 10 min to 1 min winds. For more precision then the ratio of 1.136 should be used. OTOH at the level of windspeeds we are talking about, most anemometers have sufficient "slop" as I call it that precision is not called for.

Steve

OK, cool. Thanks, Steve. Since I'm trying to be accurate, I guess I'll start using the 1.136-- even though it is kind of a pain in the azz. (The nice thing about 1.15 is that it's the same as the kt-->mph conversion factor, and of course I have that particular multiplication table 100% memorized after all these years. )

[HurricaneJosh]

Madagascar Cyclones Since 2000

For fun (and because I'm a major nerd) I did some research on Madagascar cyclones using Jorge's very cool tracking gadget. (I encourage everyone to use this tool over other ones (like Unisys)-- it's really excellent, and the data are very accurate-- straight from the sources.)

I decided just to concentrate on cyclones hitting Madagascar since 2000, as this last decade has been a very active period for the island nation. For the period 2000-2009, Madagascar had:

* 12 hurricane landfalls

* 6 major-hurricane landfalls

* 1 Cat-5 landfall

The map below shows the landfall points of all the majors. As kush has pointed out previosuly, the NE portion of the island seems to be a magnet for intense landfalls-- so the second map zooms in on that region. (Cyclone Bingiza from last week is another example of a major landfall on the NE coast.) Majors can hit the W coast (like Fanele 2009), but it happens much less often.

Not mentioned in these stats is a very near miss by another Cat 5-- Hary 2002-- which passed just offshore of that same NE region.

The large port city of Toamasina (pop. ~180K)-- on the E/C coast-- has been very lucky over the last decade, with no direct hits from any hurricane-strength cyclones. And the only 'canes to even come within 20 mi of the city in the last 30 yrs are Honorinina 1986 (Cat 1) and Geralda 1994 (Cat 3)-- so they've just been waaaaay lucky.

Note: Data are from Meteo France (La Reunion)-- the official agency for this region. All wind references are 1-min, converted from the original 10-min using a factor of 1.136. All scale references are the USA (SS) scale.

[HurricaneJosh]

Back to Australia... That Kimberley low should brew into a cyclone and threaten the Pilbara in a couple of days.

Adam, what are you expecting from this one?

[am19psu]

Back to Australia... That Kimberley low should brew into a cyclone and threaten the Pilbara in a couple of days.

Adam, what are you expecting from this one?

A track closer to the coast than the BoM. I only made it a mandarin in my update this morning. If it develops, and it stays over water, it could end up being pretty strong, because it's not going to be moving fast, but I left it festering over land for the most part.

[HurricaneJosh]

A track closer to the coast than the BoM. I only made it a mandarin in my update this morning. If it develops, and it stays over water, it could end up being pretty strong, because it's not going to be moving fast, but I left it festering over land for the most part.

Ugh, it's like Carlos II.

If it takes a track like the BoM's, however, it could get interesting? Is that what you're suggesting?

[am19psu]

Ugh, it's like Carlos II.

If it takes a track like the BoM's, however, it could get interesting? Is that what you're suggesting?

Yup. I mean, I'm talking about the difference of 50 mi and a track parallel to the coast, so their forecast is probably just as likely as mine.

[k***]

So lame.

[HurricaneJosh]

So lame.

It has potential.